Many different medical procedures involve the use of tethers, and some such medical procedures further involve tensioning the tethers. For example, tethers may be used to tighten or compress tissue (e.g., by bringing two pieces or sections of tissue together). The tissue may, for example, be soft tissue, such as muscle tissue or fat tissue. In some cases, a mitral valve that is experiencing mitral regurgitation may be repaired by deploying tethered anchors into tissue in the vicinity of the valve, and tensioning the tether. Tensioning the tether can provide a cinching effect that brings the anchors closer together, thereby reducing the circumference of the valve and alleviating the mitral regurgitation. Exemplary devices and methods for mitral valve repair are described, for example, in U.S. Patent Application Publication Nos. US 2006/0190030 A1, US 2006/0122633 A1, and US 2008/0172035 A1, all of which are hereby incorporated by reference in their entirety.
If a tether is tensioned too much in a tissue repair procedure, then the tissue may become damaged. Alternatively, if a tether is not sufficiently tensioned, then the underlying problem may not be fixed. Additionally, in minimally invasive catheter-based procedures in which the target site is located remotely from the incision site, it may be difficult to control the tension of a tether that is deployed at the remote site.
Accordingly, it would be desirable to provide devices, methods, and kits for tensioning a tether relatively precisely and/or efficiently. Moreover, it would be desirable to provide devices, methods, and kits that allow for adjustable tether tensioning. It would further be desirable for such devices, methods, and kits to provide for other forms of manipulation of the tether (e.g., by locking and/or cutting the tether).